King Arthur Building Playsets Featuring MicroMotion By Mega Bloks From Mega Brands Shop now for Mega Bloks King Arthur Building Playsets From Mega Brands. Choose from a huge variety of King Arthur building sets including the Battle Action Castle 96121, Attack Action Warship 96120, Battle Action Bridge 96118, Lamorak Beast Slayer 96112, Gawain Dragon Duel 96113, Sir Gareth and Skarsgar 96101, Melok and Iancepesade 96102, Sir Gaheris and LCP 96103, Breunor 96104 and Sir Kay 96105. These awesome King Arthur building sets are sure to entertain your child for hours. Some sets now feature MicroMotion that allow you to engage in realistic battle.